Gravity constraints on the western limit of the Semail Ophiolite in the northwestern Oman Mountains

The Oman Mountains comprise a number of thrust sheets each of which has been emplaced from SW to NE onto the Tethyan rifted continental margin of the Arabian plate. The highest of these thrusts is the Semail ophiolite complex, a massive wedge of oceanic crust and mantle of Cenomanian-Turonian (c. 95-98 Ma) age that formed above an intra-oceanic subduction zone. Although the ophiolite is one of the world's best known examples, its geometry and emplacement mechanisms are not well understood. The aim of this project is to use geophysical methods to determine the shape of the western, leading, edge of the ophiolite beneath the frontal fold and thrust belt and adjacent foreland basin. The project, which will be a collaborative one with Prof. Ali at the Petroleum Institute in Abu Dhabi, will involve the acquisition of closely spaced gravity and field geological data. These data will be integrated with existing magnetic and seismic data in order to determine the sub-surface geometry of the ophiolite and constrain its emplacement mechanism.

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